I’m looking to convert to gen 2 controller. I currently have a Rainbird ESP 12-LX Plus that runs 12 zones. It’s roughly 10 years old and is well past its prime.

As I looked behind the cover, I have 16 wires. I was wondering if anyone has an idea how to wire that appropriately to a 16 zone controller. I’m uncertain why I have more wires than zones. Appreciate any help!!

@deannd - I don’t believe the wires connected to zones 13, 14, 15 and 16 are doing anything as there are no electrical components for those ports installed on the PC board.

I’d go monkey see, monkey do. In other words take the wire in terminal 1 on the Rainbird and move it to port 1 on the Rachio. The two white wires on the Common in the Rainbird go to C on the Rachio. I’m assuming there is a rain sensor in the Sensor port, so if that is being moved to the Rachio then the red and yellow wires will go to S1 (be sure to turn on the rain sensor option in the application) and SP. Finally, ignore the black and red wires in the 24 VAC terminals as Rachio has their own transformer - but do trace them back and unplug that vampire from the wall socket.

Welcome to the Rachio community and let us know if there are any more questions. I think the original installer was just making a neat install by hooking up the unused field wires to terminals.

I want to also ask about a similar rainbird. I have ESP-24lx plus. I only have 9 zones. I just bought the house and I’m not sure if we have a rain sensor. Here is what the current wiring looks like. I will do what you said about about the transformer and c wires. Any other advice based on this picture?

You have a relatively straight forward switch over ahead of you, so no worries

As you’ve already mentioned, the thick orange wires going into the 24VAC terminals, as well as the thick green wire going into GND terminal, should be disconnected, you will no longer require any of them.
Don’t worry about the yellow jumper wire connected to SENSOR, that is just how your rainbird used to operate, it does not look like you have a rain sensor.
You have two white common wires, I’d recommend to connect them to separate C terminals of your new Rachio.
You also have two Master Valve wires (now sure why two, but it is what it is). Connect both of them to the M terminal of your rachio (I would twist them together if possible and connect them as one). Do not forget to enable master valve within the Rachio’s setup.
Finally just go down the line and move the zone wires from rainbird’s terminals 1 through 9 to Rachio’s terminals 1 through 9. Order should not be critical here, you will probably end up renaming the zones during the Rachio’s setup.